The only extreme risk is listening to anything you’ve said.
As I’ve and many others has brought from eBay over many years without issue, shows that it’s not “extreme risk
I’m not questioning buying anything on eBay, but when you get into expensive “health” related devices such as hearing aids - eBay is not ideal. Furthermore anyone would have to be a complete fool to think an aid they bought through a third party on eBay would be covered under warranty. You’re barking up the wrong tree tenkan.
I’ve dealt with both Phonak/unitron and ReSound directly, you can also check directly with the manufacturer with the serial numbers for HAs,
Now you’re throwing more stuff on the wall and it’s not sticking. Solid majority of manufacturers do not deal/take calls from hearing aid users. Their mainly set up to communicate through HA dealers/Audis and not John Q. Public. If you think someone can buy a HA on eBay and then have a person to person discussion with Phonak or ReSound - good luck with that. You won’t get far at all before Phonak and ReSound rep says “they only deal with HA suppliers and Audis directly” and certainly don’t want to discuss some ill-thought out HA purchase made on (throw the dice) eBay.
In fact many HA manufacturers don’t even have customer service, since they would prefer anyone with a hearing loss get answers from a trained Audi, hearing aid dealer, , etc.
If you don’t believe me - Google it.
You’re ignoring this member’s posts.